Does childbirth cause psychiatric disorders? A population-based study paralleling a natural experiment

Area of Science:

• Psychiatry
• Reproductive Medicine
• Epidemiology

Background:

• Childbirth is linked to a higher incidence of first-time psychiatric episodes.
• The role of unwanted pregnancy as an etiologic factor is debated.
• The impact of planned pregnancy on postpartum psychiatric episodes remains unclear.

Purpose of the Study:

• To determine if childbirth directly causes psychiatric episodes.
• To investigate whether planned pregnancies reduce the risk of postpartum psychiatric episodes.

Main Methods:

• A cohort study utilized Danish population registers of women undergoing in vitro fertilization (IVF) from 1994-2005.
• Compared psychiatric episode onset in parents versus childless individuals.
• Incidence rate ratios for first psychiatric inpatient or outpatient treatment were the primary outcome measures.

Main Results:

• The incidence rate of psychiatric disorders within 90 days postpartum was 11.3 per 1000 person-years for mothers versus 3.8 for women not giving birth.
• IVF-treated mothers showed a nearly threefold increased risk of postpartum psychiatric episodes (IRR = 2.9) compared to childless women.
• The risk of psychiatric episodes decreased after 90 days postpartum (IRR = 0.9).

Conclusions:

• Childbirth is associated with new-onset psychiatric disorders in mothers.
• Planned pregnancies, including those conceived via IVF, do not mitigate the risk of postpartum psychiatric episodes.
• The findings suggest childbirth itself is a significant risk factor for initial psychiatric episodes.